In IEEE 802.16 standards, base stations (BS) do not communicate with each other over the air interface. Instead, communication between BSs is often supported though backbone (or backhaul) connections. In all existing cellular standards (e.g., 2G, 3G, WiMAX, LTE, LTE-Advanced), base stations may only be linked to each other through dedicated connections such as optical cable or microwave radio.
However, there are situations when it is useful to allow BSs to exchange data/signaling over the radio channel. For example, when one BS experiences backhaul failure and needs to rely on another for core network connectivity, exchange of data/signaling between the two BSs over the radio channel may be required.
In IEEE 802.16.1 a system requirements, single point of failure such as high-reliability base station (HR-BS) or high-reliability relay station (HR-RS) shutdown or backhaul disruption may occur.
Thus, there is a need to provide base stations seeking to address at least the problem mentioned above, for example, to maintain network connectivity and to allow BS to BS communications during single point of failure.